4pSP24. Perception of syllable-initial English stops by native Korean
listeners.

Duration of attenuation in the region of the first formant (F1 cutback)
and relative level of aspiration energy are known to be significant acoustic
cues used to distinguish voiced from voiceless English stop consonants in
initial position. This experiment was designed to test whether Korean listeners
distinguish English stops on the same bases as native English listeners. In an
identification task, 72 stimuli from six continua ranging perceptually from
/da/ to /ta/ were presented to 12 Korean and 12 English subjects. Stimuli were
synthesized using a parallel formant synthesizer and varied in duration of F1
cutback (5--82 ns in 7-ms steps), relative amplitude of prevocalic aspiration
energy, and fundamental frequency (100, 125, and 150 Hz) of vocalic energy.
Longer F1-cutback durations and greater aspiration intensity both significantly
increased the proportion of voiceless /ta/ responses for both Korean and
English subjects. Only Korean subjects labeled more stops as voiceless when
fundamental frequency was higher. [Work supported by NIDCD grant DC-00719 and
NSF grant DBS-9258482.]